【作者】 谢珊；

【导师】 李小明； 曾光明；

【作者基本信息】 湖南大学 ， 环境工程， 2004， 硕士

【摘要】 水环境中氮元素的大量积累导致了水环境质量的严重恶化，采用有效的防治措施化解这一危害，是目前亟待解决的问题。固定化微生物处理技术是近几年发展起来的废水处理新技术，它除了可以用于重金属废水、难降解有毒有机废水和含磷废水的处理外，也可以有效地去除废水中的氨氮。利用固定化微生物技术中的自身固定化技术培养好氧颗粒污泥，实现同步硝化反硝化脱氮具有其独特的优越性和广泛的益处，已成为了生物脱氮研究的热点。 本课题立足于国内外生物脱氮研究的最新研究成果，以普通活性污泥作为接种污泥，在序批式反应器中采用逐渐减少污泥沉降时间的方法造成选择压，培育出了好氧颗粒污泥。在成功培养好氧颗粒污泥的基础上，研究SBR系统中有厌氧段和无厌氧段两种运行模式、不同COD／NH₄—N比、不同溶解氧条件等因素对好氧颗粒污泥脱氮速率的影响，深入探讨好氧颗粒污泥的脱氮特性。 实验结果表明通过逐步减小污泥沉降时间，提高污泥临界沉降速度的方法，活性污泥可凝聚成团，形成沉降性能优越的颗粒化污泥。好氧颗粒污泥外观呈橙黄色，粒径集中在0.5-0.8mm左右，污泥体积指数为11.7ml／g，MLSS高达9.4g／L。颗粒污泥具有良好的水力强度，较高的容积负荷和良好的沉降性能，对生活污水中的氮以及COD均有很好的去除能力。 有厌氧段和无厌氧段运行模式比较可以发现，无厌氧段的氨氮去除速度比有厌氧段的要快得多。不同碳氮比实验的结果显示，碳氮比越大，总无机氮去除率越高，当碳氮比由6升高到14时，总无机氮去除率由40.3％上升到74.5％。采用分段函数的方法对不同碳氮比下的氨氮去除曲线进行分段拟和，发现其具有相当好的线性化特征，且曲线斜率对应着该阶段的氨氮去除速率。减低平均溶解氧值、采用间歇曝气代替连续曝气更有助于提高总无机氮去除率，节省曝气能源消耗。更多还原

【Abstract】 Accumulation of ammonia in water environment has induced serious deterioration to the quality of water environment. It is a problem that should be solved by using proper measure to prevent the deterioration without delay. The wastewater treatment technology with immobilized microorganism is a new technique developed within these years, which can not only be used to dispose the wastewater with heavy metal, poisonous organic wastewater as well as the wastewater with phosphorus, but also be applied to remove ammonia. Cultivating aerobic granular sludge to realize simultaneous nitrification and denitrification by using self-immobilized microorganism technology is of special advantage and comprehensive benefit, which has become the highlight in the biological de-nitrogen study.Based on the latest research findings on biological nitrogen removal in both domestic and abroad, aerobic granular sludge has been cultivated with the method of decreasing sludge sedimentation time gradually to produce selective pressure by using normal activated sludge as inoculating sludge. After successfully cultivating aerobic granular sludge, we studied the running modes, COD/NH4 - N ratio, DO condition and discussed their effect on nitrogen removal efficiency, then the characteristic of nitrogen removal of aerobic granular sludge is greatly studied.The experiment results show that the floc of activated sludge can flocculate together and form aerobic granular sludge with good settling performance by reducing the sludge sedimentation time and elevating the critical sedimentation velocity of sludge gradually. The aerobic granular sludge appears orange-like granule with the average diameter ranging from 0.5mm to 0.8mm, the Sludge Volumetric Index (SVI) and the Mixed Liquid Suspended Solid (MLSS) are as high as 11.7ml/g and 9.4g/L, respectively. Compared with normal activated sludge, this aerobic granular sludge is of higher hydraulic intensity, volumetric charge and better sedimentation ability, and it can remove nitrogen and COD in domestic wastewater with high efficiency.Compared with different running modes (with and without anaerobic phase) it is found that the ammonia removal rate of phase mode without anaerobic phase is much higher than that of the mode with anaerobic phase. The total inorganic nitrogen (TIN) removal efficiency has also been studied under different COD/NH4-N ratios. The results show that the higher the COD/NH4-N ratio, the greater the TIN removal efficiency. While the COD/NH4 -N ratio increases from 6 to 14, the TIN removalefficiency rises from 40.3% to 74.5%. The profiles of ammonium removal in different ratios of COD/NH4-N (6,10,14) is proved to fit quite well with the linear regression equations that simulate the process by dividing the whole aeration period into two phases: the feast and the famine phase. The slopes of the lines correspond to the ammonia removal rate in these two phases. Reducing DO and replacing the continuous aeration with periodic aeration can benifit TIN removal efficiency and the energy source saving during the aeration period.更多还原